Gastrosidin (Tablets) Instructions for Use

ATC Code

A02BA03 (Famotidine)

Active Substance

Famotidine (Rec.INN registered by WHO)

Clinical-Pharmacological Group

Histamine H₂-receptor blocker. Antiulcer drug

Pharmacotherapeutic Group

H2 histamine receptor blocker

Pharmacological Action

Third-generation histamine H₂-receptor blocker. Suppresses the production of hydrochloric acid, both basal and stimulated by histamine, gastrin, and to a lesser extent, acetylcholine.

Simultaneously with the decrease in hydrochloric acid production and the increase in pH, it reduces pepsin activity.

The duration of action after a single dose depends on the dose and ranges from 12 to 24 hours.

Pharmacokinetics

After oral administration, it is rapidly but incompletely absorbed from the gastrointestinal tract.

C_max in blood plasma is reached within 2 hours. Bioavailability is 40-45% and changes insignificantly in the presence of food.

T_1/2 from plasma is about 3 hours and increases in patients with impaired renal function. Protein binding is 15-20%.

A small part of the active substance is metabolized in the liver to form famotidine S-oxide. The majority is excreted unchanged in the urine.

Indications

Treatment and prevention of recurrences of gastric and duodenal ulcers, reflux esophagitis, Zollinger-Ellison syndrome, diseases and conditions accompanied by increased gastric juice secretion, prevention of erosive and ulcerative lesions of the gastrointestinal tract against the background of NSAID use; bleeding from the upper gastrointestinal tract (for intravenous administration, as part of complex therapy).

ICD codes

Dosage Regimen

Tablets

Individual, depending on the indications.

Orally for treatment, 10-20 mg 2 times/day or 40 mg once a day. If necessary, the daily dose can be increased to 80-160 mg. For prevention – 20 mg once a day before bedtime.

For intravenous administration, a single dose is 20 mg, the interval between administrations is 12 hours.

If creatinine clearance is less than 30 ml/min or with a serum creatinine concentration of more than 3 mg/dl, the dose is recommended to be reduced to 20 mg/day.

Adverse Reactions

From the digestive system: possible lack of appetite, dry mouth, taste disorders, nausea, vomiting, abdominal bloating, diarrhea or constipation; in some cases – the development of cholestatic jaundice, increased levels of transaminases in blood plasma.

From the central nervous system: possible headache, increased fatigue, tinnitus, transient mental disorders.

From the cardiovascular system: rarely – arrhythmias.

From the hematopoietic system: very rarely – agranulocytosis, pancytopenia, leukopenia, thrombocytopenia.

From the musculoskeletal system: possible muscle pain, joint pain.

Allergic reactions: possible skin itching, bronchospasm, fever.

Dermatological reactions: possible alopecia, acne vulgaris, dry skin.

Local reactions: irritation at the injection site.

Contraindications

Hypersensitivity to famotidine; Pregnancy, breastfeeding period; children under 18 years of age.,

Use in Pregnancy and Lactation

Contraindicated for use during pregnancy and lactation.

Famotidine is excreted in breast milk.

Use in Hepatic Impairment

Use with caution in patients with impaired liver function.

Use in Renal Impairment

Use with caution in patients with impaired renal function.

Pediatric Use

Contraindicated for use in children and adolescents under 18 years of age.

Special Precautions

Use with caution in patients with impaired renal and liver function.

Before starting treatment, it is necessary to exclude the possibility of a malignant disease of the esophagus, stomach, or duodenum.

Does not change the activity of liver microsomal enzymes.

An interval of at least 1-2 hours should be observed between taking antacids and famotidine.

Drug Interactions

When used concomitantly with anticoagulants, the possibility of increased prothrombin time and the development of bleeding cannot be excluded.

When used concomitantly with antacids containing magnesium hydroxide and aluminum hydroxide, a decrease in the absorption of famotidine is possible.

When used concomitantly with itraconazole, a decrease in the plasma concentration of itraconazole and a decrease in its effectiveness are possible.

When used concomitantly with nifedipine, a case of decreased minute volume and cardiac output was described, apparently due to an enhancement of the negative inotropic effect of nifedipine.

When used concomitantly with norfloxacin, the plasma concentration of norfloxacin decreases; with probenecid – the plasma concentration of famotidine increases.

When used concomitantly, a case of increased plasma concentration of phenytoin with the risk of toxic effects was described.

When used concomitantly, the bioavailability of cefpodoxime decreases, apparently due to a decrease in its solubility in the gastric contents when the pH of gastric juice increases under the influence of famotidine.

When used concomitantly with cyclosporine, some increase in the plasma concentration of cyclosporine is possible.

Storage Conditions

Store at 2°C (36°F) to 25°C (77°F). Keep in original packaging, protected from light. Keep out of reach of children.

Dispensing Status

Rx Only

Important Safety Information

This information is for educational purposes only and does not replace professional medical advice. Always consult your doctor before use. Dosage and side effects may vary. Use only as prescribed.